2002 Subaru Forester Hesitation/Stall

subaru
stall
forester
hesitation

#1

My 2002 Subaru Forester has just over 65,000 miles and has recently started having a randomly occurring problem of hesitation when idling and when taking off from a stop. Here’s the scenario:



When stopped at a sign/light the engine can’t seem to idle consistently. It goes into a cycle of nearly dying, reviving, dying, reviving, etc. It is like the opposite of revving the engine. In fact just yesterday it actually died for the first time when this was happening. When it’s time to go I press the gas and the car will hesitate, like the gas isn’t getting to the engine. Sometimes it will lurch a bit with the dying/reviving cycle. I have to kind of tease the gas pedal a bit to get it to go and when it kicks in there is a sudden jolt of power.

The hesitation problem surfaced last winter but was random and occurred so infrequently that I never bothered to have it checked. As the summer came around the problem vanished entirely. Now that its getting colder again the hesitation has come back with a vengeance, however, the near-stall problem is completely new. To make the problem worse, as I said above, the trouble occurs randomly - sometimes it drives perfectly, sometimes it won’t!



I had the car at a local shop for a full week during which time they replaced the fuel regulator and air-flow sensor to no avail. They checked all of the electrical systems - they’re fine. The check engine light has not turned on and there are no codes that come up in a diagnostic.

I’ve done a bit of online research and have found a few mentions of similar problems here and there. Most of these problems don’t have adequate answers and some describe battles with local dealerships over the issue itself.



I also have a sub-question:

Around 45,000 miles I needed to replace the head gasket on this car as well. This is a known problem on Foresters of this era, although I had to finagle a three-part deal with Subaru Warranty, the local dealer, and myself to get the repair covered. Part of the deal required that I pay for the 60,000 mile maintenance then (when it only had 45,000 miles!).

I have also already had to replace the rear oxygen sensor!

When does this all add up to a late-blooming lemon?



Any advice would be greatly appreciated!


#2

I have exactly the same model/year and exactly the same problem… Have brought in to my (Firestone) mechanic three times and the last time they sent me to an independent mechanic b/c they thought an exhaust leak was the problem. The ind. mech. couldn’t diagnose either. I saw some other posts here on Cartalk that replacing the TPS (Throttle Position Sensor?) resolved the problem - but when I called our mechanic, they said they didn’t think that would resolve it.

I hope it is the answer - it would be great if that’s all it is (one person said it cost $142 parts and labor - I can handle that). Anyone else have advice?